Nope! Everything happens right in your browser. Your files never leave your device, so they remain completely private.
There's no hard limit set by the site, but very large files may slow down your browser or cause it to crash. If you're converting a massive PDF, try breaking it into smaller chunks first.
Low (72 DPI) — Smaller file size, fine for screen viewing. Default (150 DPI) — Balanced quality and size, good for most uses. High (300 DPI) — Best for printing, but produces larger files.
If your PDF has multiple pages, each page is converted into a separate PNG file. You'll get one download per page. Make sure your browser allows multiple downloads!